Ball bearing assemblies with race rings made of sheet metal are not new per se. These known assemblies are simple and inexpensive to manufacture and are primarily employed where the demands for carrying capacity and precision are not too great. Typically, such bearing assemblies are manufactured with the outer and inner race rings pressed separately to their final, finished shape and then assembled in a known manner upon insertion of the balls. Various bearing types, such as deep groove or angular contact ball bearings, may be utilized. Because the race rings are initially shaped to final form prior to insertion of the balls, the bearing assemblies typically employ only a single row of balls. This allows for ease of assembly. However, double row bearings wherein the outer race ring is split so as to facilitate assembly are also known. For example, a bearing having a split outer race ring is disclosed in U.S. Pat. No. 3,732,606. Also, German Patent No. 25 18 129 describes a double row, angular contact ball bearings with race rings angularly adjustable relative to one another.
Bearing assemblies may be manufactured from a piece of sheet metal through a number of different methods. The most common method of manufacture involves pressing or rolling the race rings one at a time. However, the rings may also be shaped simultaneously during the process of assembling the bearing. U.S. Pat. No. 3,657,781 describes such a method of manufacturing a single row, deep groove ball bearing. Initially, two annular pieces of sheet metal are partially shaped by a known device, such as a shaping tool. In addition, a row of balls which are retained in position by means of shaping tool during the shaping process, also act to partially shape the race rings. But because of the demands placed upon the tool and its design, the method is complicated and expensive. A further drawback of this known method is that it can only be used to manufacture single row ball bearings. Insertion of a second row of balls is not possible because an additional raceway cannot be formed by means of the tool and balls.